探讨孕妇血清叶酸、维生素B12、铁蛋白水平(以下简称为"贫血3项指标")及其意义。

选择2017年1月至2019年1月，于滨州市第二人民医院进行产前检查并分娩的早、中、晚孕期孕妇，以及进行健康体检的育龄期非妊娠女性各130例为研究对象，分别纳入早、中、晚孕期组及对照组，并对各组受试者进行贫血3项指标检测。采用单因素方差分析及SNK-q法，对4组受试者贫血3项指标检测结果分别进行总体及两两比较；采用χ²检验，对早、中、晚孕期组孕妇贫血3项指标异常(叶酸/维生素B12/铁蛋白这3种物质之一缺乏)、贫血发生率及妊娠并发症发生情况分别进行总体及两两比较；采用独立样本t检验，分别对不同孕期组贫血3项指标异常与正常孕妇分娩新生儿出生时生长发育指标进行比较。本研究遵循的程序符合2013年新修订的《世界医学协会赫尔辛基宣言》要求，所有受试者签署临床研究知情同意书。

①早孕期组与对照组受试者贫血3项指标比较，差异均无统计学意义(P>0.05)。中、晚孕期组受试者血清叶酸、维生素B12及铁蛋白水平分别为(8.8±2.4) nmol/L、(238.2±103.8) pmol/L及(41.5±10.3) μg/L，(6.3±1.2) nmol/L、(134.2±23.5) pmol/L及(15.7±6.8) μg/L，均分别低于早孕期组和对照组的(12.9±3.4) nmol/L、(353.7±122.9) pmol/L及(77.7±15.1) μg/L，(13.6±3.8) nmol/L、(376.9±128.7) pmol/L及(80.3±16.3) μg/L，并且差异均有统计学意义(中孕期组vs早孕期组：q＝16.226、12.702、32.478，均为P<0.001；中孕期组vs对照组：q＝18.997、15.254、34.810，均为P<0.001；晚孕期组vs早孕期组：q＝26.120、24.140、55.625，均为P<0.001；晚孕期组vs对照组：q＝28.891、26.691、57.957，均为P<0.001)。随着孕龄增加，孕妇贫血3项指标逐渐下降，并且差异均有统计学意义(P<0.05)。②晚孕期组孕妇贫血3项指标异常发生率、叶酸缺乏性巨幼细胞性贫血及缺铁性贫血发生率，以及贫血总发生率，均分别高于早、中孕期组；中孕期组上述指标发生率，均高于早孕期组，并且上述差异均有统计学意义(P<0.05)。③晚孕期组孕妇妊娠期高血压疾病、心肌缺血/损害、胎儿异常及妊娠并发症总发生率，均分别高于早、中孕期组，并且差异均有统计学意义(P<0.05)。早孕期组与中孕期组上述妊娠并发症发生率比较，差异均无统计学意义(P>0.05)。④早、中、晚孕期组孕妇中，贫血3项指标异常者分娩新生儿的身长，均短于正常者分娩新生儿，并且差异均有统计学意义(P<0.05)；晚孕期组孕妇中，血清铁蛋白水平低者分娩新生儿的出生体重，轻于正常者分娩新生儿，并且差异有统计学意义(P<0.05)。除早孕期组孕妇中维生素B12缺乏者与正常者及晚孕期组孕妇中铁蛋白缺乏者与正常者分娩新生儿头围比较，差异无统计学意义(P>0.05)外，其余情况下，贫血3项指标异常孕妇分娩新生儿出生时头围，均小于正常者分娩新生儿，并且差异均有统计学意义(P<0.05)。

随着孕妇孕龄增长，其血清叶酸、维生素B12及铁蛋白水平降低，贫血及妊娠并发症发生风险增加。各孕期孕妇贫血3项指标异常，均可能影响胎儿的生长发育。

To investigate serum levels of folic acid, vitamin B12 and ferritin (this study is referred to as " 3 parameters of anemia" ) of pregnant women and their significances.

There were 130 pregnant women in early, middle and late pregnancy, respectively, who underwent prenatal examination and childbirth in Binzhou Second People′s Hospital from January 2017 to January 2019, and 130 non∑- pregnant women of childbearing age who underwent physical examination in the same hospital at the same time, were selected as research subjects. According to gestational age and pregnant or not, they were divided into early pregnancy group, middle pregnancy group, late pregnancy group and control group, respectively. These 3 parameters of anemia of all subjects were measured. These parameters of anemia among four groups were overall compared by one-way ANOVA and further compared by SNK-q method. Chi-square test was used to make overall and pairwise comparison of incidence of 3 parameters of anemia abnormal (deficiency among one of three substances of folic acid, vitamin B12 and ferritin), anemia and complications during pregnancy among pregnant women in early, middle and late pregnancy group. Independent-samples t test was used to compare neonatal growth and development indexes at birth between neonates of pregnant women with 3 parameters of anemia abnormal and normal in different pregnancy group, respectively; The procedure followed in this study was in accordance with the World Medical Association Declaration of Helsinki revised in 2013, and all subjects signed the informed consent forms for clinical research.

① There were no significant differences in 3 parameters of anemia of subjects between early pregnancy group and control group (P>0.05). The serum levels of folic acid, vitamin B12 and ferritin in middle pregnancy group and late pregnancy group were (8.8±2.4) nmol/L, (238.2±103.8) pmol/L and (41.5±10.3) μg/L, and (6.3±1.2) nmol/L, (134.2±23.5) pmol/L and (15.7±6.8) μg/L, respectively, which were lower than those of (12.9±3.4) nmol/L, (353.7±122.9) pmol/L and (77.7±15.1) μg/L in early pregnancy group and those of (13.6±3.8) nmol/L, (376.9±128.7) pmol/L and (80.3±16.3) μg/L in control group, respectively, and the differences were statistically significant (middle pregnancy group vs early pregnancy group: q=16.226, 12.702, 32.478, all P<0.001; middle pregnancy group vs control group: q=18.997, 15.254, 34.810, all P<0.001; late pregnancy group vs early pregnancy group: q=26.120, 24.140, 55.625, all P<0.001; late pregnancy group vs control group: q=28.891, 26.691, 57.957, all P<0.001). With the increase of gestational age, 3 parameters of anemia decreased gradually, and the differences were statistically significant (P<0.05). ② The incidence of 3 parameters of anemia abnormal, incidence of folic acid deficiency megaloblastic anemia and iron deficiency anemia, and total incidence of anemia of pregnant women in late pregnancy group were higher than those in early and middle pregnancy group, respectively; The incidence of those indexes above mentioned in middle pregnancy group were higher than those in early pregnancy group, and all the differences above were statistically significant (P<0.05). ③ The incidence of pregnancy induced hypertension, myocardial ischemia/damage, fetal abnormalities and total complications of pregnant women in late pregnancy group were higher than those in early and middle pregnancy group, respectively, and the differences were statistically significant (P<0.05). There were no significant differences in incidence of pregnancy complications mentioned above between early pregnancy group and middle pregnancy group (P>0.05). ④ Among pregnant women in early, middle and late pregnancy groups, each group showed that the body length of newborns delivered by pregnant women with 3 parameters of anemia abnormal were shorter than those of normal, and the differences were statistically significant (P<0.05). In late pregnancy group, the birth weight of newborns delivered by pregnant women with ferritin deficiency was lighter than that of normal, and the difference was statistically significant (P<0.05). Except for there were no significant differences in head circumference at birth of newborns between delivered by pregnant women with vitamin B12 deficiency and normal in early pregnancy group, and pregnant women with ferritin deficiency and normal in late pregnancy group (P>0.05). In other cases, the head circumference at birth of newborns delivered by pregnant women with 3 parameters of anemia abnormal were smaller than those of normal, and the differences were statistically significant (P<0.05).

The more gestational age is, the lower levels of serum folate, vitamin B12 and ferritin, and the higher risk of anemia and pregnancy complications are. During different pregnancy period, if pregnant women with one of 3 parameters of anemia abnormal may affect the growth and development of fetus.